Hydrogen storage device

ABSTRACT

The present invention discloses a hydrogen storage device. The hydrogen storage device includes a first casing, at least one hydrogen container, at least one stress buffering unit, and a second casing. The hydrogen container is set inside the first casing. The stress buffering unit is set between the hydrogen container and the first casing. The second casing surrounds the first casing forming a second space to contain heat transfer media, thereby controlling the temperature of the hydrogen container. While the hydrogen storage materials loaded in the hydrogen container absorb hydrogen gas, the stress buffering unit can eliminate the stress caused by the volume expansion of the hydrogen storage materials so as to prevent the first casing from distortion and deformation. Thus, the hydrogen gas can be stored efficiently and safely.

BACKGROUND OF THE INVENTION

1. Technical Field

The present invention relates to hydrogen storage devices, and more particularly, to a hydrogen storage device that stores hydrogen gas efficiently and safely.

2. Description of Related Art

Currently, hydrogen gas, which is used in fuel batteries, need to be stored in hydrogen storage devices. However, hydrogen gas is typically stored by means of hydrogen storage materials. One type of such hydrogen storage materials is metal hydride, which, in comparison with erstwhile approaches where hydrogen gas was liquefied under high pressure, is less likely bring about the problem of leakage and related dangers caused by mass hydrogen gas.

Typically, existing hydrogen storage devices are made by filling hydrogen storage alloy powder in the device with a certain vacant space reserved for the expansion of the hydrogen storage alloy powder. When absorbing hydrogen gas, the hydrogen storage alloy powder expands in volume and the particles of the powder jostle mutually. Consequently, the casing of the hydrogen storage device may deform due to the stress caused thereby. In addition, absorption of hydrogen accompanies the exothermic effect, which raises the temperature in the device and in turn reduces the efficiency of absorption. Hence, how to effectively disperse the generated heat is also an issue to be considered in designing hydrogen storage devices.

Moreover, after repeated absorption and desorption of hydrogen, incineration and explosion are likely to happen to the hydrogen storage alloy powder. At this time, if the container receiving the hydrogen storage alloy powder is not designed with appropriate reserved space and fixing means, the overall service life of the hydrogen storage device can be significantly reduced. In view of the foregoing problems, designing a hydrogen storage device with reduced material costs and enhanced storage capacity of hydrogen storage alloy powder, that is also capable of effective long-term hydrogen gas storage, while ensuring the safety, efficiency, economic benefits, and convenience of hydrogen storage is an aim to be achieved.

BRIEF SUM MARY OF THE INVENTION

The present invention provides a hydrogen storage device, which is equipped with a stress buffering unit and thereby eliminates the distortion and deformation of a hydrogen container thereof caused by expanded hydrogen storage material in hydrogen absorption.

The present invention provides a hydrogen storage device, which is provided with a flow channel that assists a heat transfer medium therein in performing heat exchange so as to modulate the temperature variation of the hydrogen storage material and in turn ensure effective absorption and desorption of hydrogen.

In order to achieve the above objectives, the present invention further provides a hydrogen storage device for storing hydrogen gas. The hydrogen storage device comprises: a first casing formed therein within a first space and formed thereon with a first opening that allows the first space to intercommunicate with an external environment; at least one hydrogen container set inside the first space for receiving a hydrogen storage material, wherein the hydrogen gas enters the first space from the external environment through the first opening and comes into contact with the hydrogen storage material for being stored; at least one stress buffering unit arranged between each said hydrogen container and the first casing for buffering a stress caused by the hydrogen storage material and acting on the hydrogen container; and a second casing surrounding the first casing to define a second space within the first casing, wherein the second casing has an inlet valve and an outlet valve that allow the second space to intercommunicate with the external environment, and a flow channel is defined between the inlet valve and the outlet valve in the second space for allowing at least one heat transfer medium to flow into the second space from the external environment through the inlet valve and to flow out of the second space through the outlet valve so that by heat exchange of the heat transfer medium, temperature of the hydrogen container is modulated.

In order to achieve the above objectives, the present invention further provides a hydrogen storage device for storing hydrogen gas. The hydrogen storage device comprises: a first casing formed therein with a first space and formed thereon with an opening that allows the first space to intercommunicate with an external environment; at least one hydrogen container set inside the first space for receiving a hydrogen storage material, wherein the hydrogen gas enters the first space from the external environment through the opening and comes into contact with the hydrogen storage material for being stored; and at least one stress buffering unit arranged between each said hydrogen container and the first casing for buffering a stress caused by the hydrogen storage material and acting on the hydrogen container.

By implementing the present invention, at least the following progressive effects can be achieved:

1. With the stress buffering unit, the hydrogen container is prevented from distortion and deformation that otherwise might be caused by stress out of volume expansion of the hydrogen storage materials during hydrogen absorption.

2. By the heat exchange of the heat transfer medium, the temperature of the hydrogen storage material is controllable and in turn, effective absorption and desorption of hydrogen can be ensured.

BRIEF DESCRIPTION OF THE DRAWINGS

A detailed description of further features and advantages of the present invention is given below so that a person skilled in the art can understand and implement the technical contents of the present invention and readily comprehend the objectives and advantages thereof by reviewing the disclosure of the present specification and the appended claims in conjunction with the accompanying drawings, in which:

FIG. 1 depicts a first embodiment of a hydrogen storage device according to the present invention;

FIG. 2 is a vertical sectional view of the hydrogen storage device taken along Line A-A of FIG. 1;

FIG. 3 is a transverse sectional view of the hydrogen storage device taken along Line B-B of FIG. 1;

FIG. 4 shows a second embodiment of the hydrogen storage device according to the present invention;

FIG. 5 provides a third embodiment of the hydrogen storage device according to the present invention;

FIG. 6 illustrates a fourth embodiment of the hydrogen storage device according to the present invention; and

FIG. 7 exhibits a fifth embodiment of the hydrogen storage device according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIG. 1 through FIG. 3, the present embodiment shows a hydrogen storage device 100 for storing hydrogen gas. The hydrogen storage device 100 includes: a first casing 10, at least one hydrogen container 20, at least one stress buffering unit 30, and a second casing 40.

As shown in FIG. 2, the first casing 10 is formed therein with a first space 11 and thereon with a first opening 12. The first opening 12 allows the first space 11 to intercommunicate with the external environment, and allows hydrogen gas to be introduced into the first space 11 therethrough. The first casing 10 may include at least one depressed portion 13, which is formed by depressing the first casing 10 inward the first space 11. The depressed portion 13 may be shaped as a column.

The hydrogen container 20, which may be a top-opened annular container, is set inside the first space 11 for receiving a hydrogen storage material. Hydrogen gas is introduced into the first space 11 from the external environment by way of the first opening 12 and comes into contact with the hydrogen storage material in the hydrogen container 20 so that the hydrogen gas is stored. The first space 11, depending on the volume thereof; may include at least two said hydrogen containers 20. In order to prevent volume expansion of the hydrogen storage material after hydrogen absorption from affecting the first casing 10 and to give the hydrogen storage material sufficient space to expand, the hydrogen containers 20 may be arranged in the first space 11 with a predetermined interval therebetween.

The hydrogen storage material may be of the high-temperature type, middle-temperature type or low-temperature type, and may be made of hydrogen storage alloy or, more particularly, metal hydride. In the meantime, different types of hydrogen storage materials may be used. For this end, each said hydrogen container 20 is configured to receive hydrogen storage materials of different characteristics independently.

The stress buffering unit 30 is arranged between each said hydrogen container 20 and the first casing 10 for buffering stress that acts on the hydrogen container 20 and is caused by the volume expansion of the hydrogen storage materials. The stress buffering unit 30 may be a spring unit 31, a sponge unit, a metal elastic piece 32 or an elastomer. As shown in FIG. 4, the stress buffering unit 30 is a spring unit 31 made of metal and serves to connect the hydrogen container 20 to a lateral wall of the first casing 10. The metal spring unit 31, in addition to its function of buffering the stress caused by the volume expansion of the hydrogen storage materials, can further provide good thermal conductivity that facilitates heat transmission of the hydrogen storage materials during absorption and desorption of hydrogen gas.

Alternatively, as shown in FIG. 5, the stress buffering unit 30 may be a metal elastic piece 32 in the form of a bent metal sheet. Therein, each metal elastic piece 32 has a camber apex 33 and two ends 34. The camber apex 33 is connected with the hydrogen container 20, and the ends 34 are fasten to the lateral wall of the first casing 10. Since the metal elastic piece 32 is made of metal and thus has resilience, it can also provide the functions of heat transmission and buffering.

Referring back to FIG. 2 and FIG. 3, the second casing 40 surrounds the first casing 10 and defines a second space 41 with the first casing 10. The second casing 40 further has an inlet valve 42 and an outlet valve 43 that allow the second space 41 to intercommunicate with the external environment. Meantime, a flow channel 44 is defined between the inlet valve 42 and the outlet valve 43 in the second space 41 for allowing at least one heat transfer medium to flow into the second space 41 from the external environment by way of the inlet valve 42 and flow out of the second space 41 through the outlet valve 43.

When the first casing 10 includes the depressed portion 13, the flow channel 44 may be made as a curved flow channel 44, and the depressed portion 13 may further include a spoiler 45. The spoiler 45 is settled on the second casing 40 and in parallel with lateral walls of the depressed portion 13 so that the heat transfer medium can flow into the depressed portion 13. Thus, heat generated by the hydrogen storage material near the center of the hydrogen storage device 100 can be also effectively dispersed through heat exchange.

As shown in FIG. 2, arrows indicate the direction of the heat transfer medium flowing in the second space 41. The heat transfer medium flows into the second space 41 through the inlet valve 42, and then passes the curved flow channel 44 composed of the spoiler 45 and the depressed portions 13 before flowing out of the second space 41 by way of the outlet valve 43. As a result the heat transfer medium can perform heat exchange to both the inner and outer hydrogen storage material in the hydrogen container 20, so as to modulate the temperature of the hydrogen container 20. Therein the heat transfer medium may be one or a combination of any of water, gas, oil and a hydrocarbon.

In the hydrogen storage device 100, temperature modulation of the hydrogen container 20 relies on heat transmission of both the first casing 10 and the second casing 40. Therefore, the first casing 10 and the second casing 40 may be independently made of different heat transfer materials. However, for further isolating the overall hydrogen storage device 100 from the external temperature, additional heat-insulation design may be adopted. As shown in FIG. 2, a heat insulation layer 50 may be further implemented to surround the second casing 40. Or, as shown in FIG. 4, a third casing 60 made of a heat transfer material independently may be additionally provided outside the second casing 40. The third casing 60 surrounds the second casing 40 and defines a third space 61 with the second casing 40. The third space 61 may also contain a heat insulation unit (not shown) for reducing the heat transmission between the external environment and the hydrogen container 20.

Referring to FIG. 6 and FIG. 7, there is another embodiment of the present invention. The hydrogen storage device 100′ includes a first casing 10, at least one hydrogen container 20, and at least one stress buffering unit 30.

As shown in FIG. 6 and FIG. 7, the first casing 10 is also formed therein with a first space 11 and formed thereon with an opening 14 that allows the first space 11 to intercommunicate with the external environment and allows hydrogen gas to be introduced into the first space 11 therethrough.

The hydrogen container 20 may be in the shape of a disk and set inside the first space 11 for receiving a hydrogen storage material. The first casing 10 may include at least two said hydrogen containers 20 that are arranged in the first space 11 with a predetermined interval therebetween. The hydrogen container 20 may independently receive hydrogen storage materials of different characteristics. Therein, hydrogen gas is introduced into the first space 11 from the external environment through the opening 14 on the first casing 10 and comes into contact with the hydrogen storage materials so that the hydrogen gas can be stored. Moreover, the hydrogen storage materials may be of the high-temperature type, middle-temperature type, or low-temperature type.

The stress buffering unit 30 is arranged between each said hydrogen container 20 and the first casing 10 for buffering stress acting on the hydrogen container 20 during absorption and desorption of the hydrogen gas. The stress buffering unit 30 may be a spring unit 31, a sponge unit, a metal elastic piece 32, or an elastomer.

As shown in FIG. 7, the stress buffering unit 30 is a spring unit 31 made of metal and connecting between the hydrogen container 20 and the first casing 10. The metal spring unit 31 can not only buffer the stress caused by the volume expansion of the hydrogen storage materials, but also provide good thermal conductivity that facilitates heat transmission of the hydrogen storage materials during absorption and desorption of hydrogen gas. The stress buffering unit 30 may alternatively be a metal elastic piece 32 composed of a bent metal sheet as shown in FIG. 5.

The foregoing embodiments are illustrative of the characteristics of the present invention so as to enable a person skilled in the art to understand the disclosed subject matter and implement the present invention accordingly. The embodiments, however, are not intended to restrict the scope of the present invention. Hence, all equivalent modifications and variations made in the foregoing embodiments without departing from the spirit and principle of the present invention should fall within the scope of the appended claims. 

1. A hydrogen storage device for storing hydrogen gas, the hydrogen storage device comprising: a first casing formed therein with a first space and formed thereon with a first opening that allows the first space to intercommunicate with an external environment; at least one hydrogen container set inside the first space for receiving a hydrogen storage material, wherein the hydrogen gas is introduced from the external environment into the first space through the first opening and comes into contact with the hydrogen storage material so that the hydrogen gas is stored; at least one stress buffering unit arranged between each said hydrogen container and the first casing for buffering a stress that is caused by the hydrogen storage material and acts on the hydrogen container; and a second casing surrounding the first casing and together with the first casing defining a second space therebetween, the second casing having an inlet valve and an outlet valve, which allow the second space to intercommunicate with the external environment, and a flow channel being defined between the inlet valve and the outlet valve in the second space for allowing at least one heat transfer medium to flow into the second space from the external environment through the inlet valve and flow out of the second space through the outlet valve, wherein heat exchange is performed by the heat transfer medium to modulate a temperature of the hydrogen container.
 2. The hydrogen storage device of claim 1, wherein the first casing includes at least one depressed portion extending inward the first space so as to make the flow channel be a curved flow channel.
 3. The hydrogen storage device of claim 2, wherein the depressed portion further includes at least one spoiler.
 4. The hydrogen storage device of claim 3, wherein the spoiler is settled on the second casing and in parallel with a lateral wall of the depressed portion.
 5. The hydrogen storage device of claim 1, wherein the heat transfer medium is one or a combination of any selected from the group consisting of water, gas, oil and hydrocarbons.
 6. The hydrogen storage device of claim 1, wherein the hydrogen container includes at least two said hydrogen containers that are arranged in the first space with a predetermined interval between the adjacent hydrogen containers.
 7. The hydrogen storage device of claim 1, wherein the hydrogen containers are configured to independently receive hydrogen storage materials of different characteristics, respectively.
 8. The hydrogen storage device of claim 1, wherein the hydrogen storage material is a high-temperature type hydrogen storage material, a middle-temperature type hydrogen storage material or a low-temperature type hydrogen storage material.
 9. The hydrogen storage device of claim 1, wherein the hydrogen storage material is hydrogen storage alloy.
 10. The hydrogen storage device of claim 9, wherein the hydrogen storage alloy is metal hydride.
 11. The hydrogen storage device of claim 1, wherein each said stress buffering unit is a spring unit, a sponge unit, a metal elastic piece or an elastomer.
 12. The hydrogen storage device of claim 1, wherein the first casing and the second casing are independently made of heat transfer materials.
 13. The hydrogen storage device of claim 1, further comprising a heat insulation layer that surrounds the second casing.
 14. The hydrogen storage device of claim 1, further comprising a third casing that surrounds the second casing and define a third space with the second casing.
 15. The hydrogen storage device of claim 14, further comprising a heat insulation unit set inside the third space for reducing heat transmission between the external environment and the hydrogen container.
 16. The hydrogen storage device of claim 14, wherein the first casing, the second casing and the third casing are independently made of heat transfer materials.
 17. A hydrogen storage device for storing hydrogen gas, the hydrogen storage device comprising: a first casing formed therein with a first space and formed thereon with an opening that allows the first space to intercommunicate with an external environment; at least one hydrogen container set inside the first space for receiving a hydrogen storage material, wherein the hydrogen gas is introduced from the external environment into the first space through the opening and comes into contact with the hydrogen storage material so that the hydrogen gas is stored; and at least one stress buffering unit arranged between each said hydrogen container and the first casing for buffering a stress that is caused by the hydrogen storage material and acts on the hydrogen container.
 18. The hydrogen storage device of claim 17, wherein the hydrogen container includes at least two said hydrogen containers that are arranged in the first space with a predetermined interval between the adjacent hydrogen containers.
 19. The hydrogen storage device of claim 17, wherein the hydrogen containers are configured to independently receive hydrogen storage materials of different characteristics, respectively.
 20. The hydrogen storage device of claim 17, wherein the stress buffering unit is a spring unit, a sponge unit, a metal elastic piece, or an elastomer. 